Needle motion for axminster looms



Dec. 28, 1937. w w ROBERTSON 2,103,825

NEEDLE MOTION FOR AXMINSTER LOOMS Filed Dec; 21, 19%

Inventor I William W. Roberison Attorney Patented Dec. 28, 1937 UNITED STATES PATENT OFFICE NEEDLE MOTION For. AXMINSTER LooMs setts Application December 21, 1936, Serial No. 116,967

6 Claims.

This invention relates to improvements in needle motions for Axminster looms and it is the general object of the invention to permit the continuous running of the heavy parts of the needle motion while at the same time permitting a dwell in theneedle movement.

I As heretofore constructed Axminster looms have had large intermittent gears with spaced sections of teeth to actuate a pinion connected to shafting and other heavy parts. As a result of this construction it has been necessary to stop and start a relatively large mass of moving parts for each insertion of the needle. The reason for the intermittent motion has been to permit the needle to remain at rest while the lay beats forwardly subsequent to the laying of weft. It is an important object of my present invention to permit the dwell in the needle motion and at the same time move the heavy parts of the mechanism continuously, thereby reducing the cost of operation and the likelihood of breakage and wear.

It has also been customary in Axminster looms to provide an oscillating segment with gear teeth to mesh with the pinion connected to the drum which actuates the cable or rope for the needle motion. In the past the segment has been so constructed that any motion thereof has required a corresponding turning of the pinion with consequent movements of the needle. It is a further object of my present invention to modify the segment as heretofore used by the addition of arcuate dwell areas to cooperate with a lock connected to the pinion. By this construction the pinion is given the requisite amount of angular motion, after which the lock comes into action and cooperates with the dwell on the segment to hold the pinion and therefore the needle stationary While the segment continues to move. These advantages are achieved without lengthening the. guide rail.

-When the needle is fully inserted into the shed the selvage shuttle passes through the loop of weft carried by the needle and this operation requires an appreciable amount of time. If desired I may also provide a dwell on the segment which operates to hold the needle stationary while fully inserted into the shed to allow more time for the selvage shuttle to loop the weft. I do not deem this an essential feature of my invention, inasmuch as the driving arm for the segment has a crank motion which gives the effect of a temporary dwell in the motion of the needle at this time. This dwell due to the crank will ordinarily suffice, but where a longer dwell is desired the second dwell on the segment can be employed.

With these and other objects in view which will appear as the description proceeds, my invention resides in the combination and arrangement of parts hereinafter described and set forth.

In the accompanying drawing, wherein a convenient embodiment of my invention is set forth,

Fig. 1 is a front elevation of the needle motion of an Ax'minster loom having my invention applied thereto,

Fig. 2 is a vertical section on line 2-2 of Fig. 1,

Figs. 3, 4, 5 and 6 are diagrammatic views showing the relation of the needle moving parts in different positions of the segment, and

Fig. '7 is a plan' view of the pinion, lock therefor and segment cooperating therewith, taken in the direction of arrow 1, Fig. 1.

Referring to the drawing, I have shown the needle frame I!) of an Axminster loom the weaving instrumentalities of which will ordinarily lie to the left of the structure illustrated in Fig. 1 and which have been omitted because they are Well understood. Supported on the upper part of the frame ii] is a needle rail l l to support and guide a needle carrier 22 which is reciprocated along the rail by a cable E3 to move a weft laying needle N. The lay extends around an inner sheave l 4 rotating on a fixed pin l5 and a drum l 6 is provided to have attached thereto one end of the cable l3. The opposite end of the cable is also secured to the drum in well-known manner and extends to the right as viewed in Fig. 1 to pass around a movable sheave H rotatably mounted as at H! on a slack taking-up arm 19 pivotal about an axis 2|. A Weight 26 connected to the arm l9 tends to move the latter to the right as viewed in Fig. 1 for the purpose of holding cable I 3 taut. The details of the structure shown at the right hand end of the rail for controlling the movable sheave I! may be the same as that shown in my prior Patent No. 1,724,315 and of itself forms nopart of my present invention.

I provide also a continuously running shaft 30 mounted in suitable bearings and having mounted thereona relatively large beveled gear 3| which meshes with a corresponding bevel pinion 32 secured to a shaft 33. The latter also rotates in appropriate bearings and has keyed thereto a crank arm 34 which may turn in a clockwise direction as indicated by arrow a in Fig. 1.

preferably though not necessarily with a uniform angular rate.

The matter thus far described is of known con- The crank arm 34 therefore rotates continuously and entirely around the periphery thereof and rep-lacing the usual intermittent bevel gear, but being similar to the gear set forth in patent to Paine 1,739,171.

A segment 40 is pivoted to the needle frame as at 4| and is attached to the crank arm 34 by a connector 42, the point of attachment between the connector and the segment being adjustable as designated generally at 43 in Fig. l to permit a moderate adjustment in the throw of the segment. A rod head 44 permits adjustment of the length of the connector 42.

The segment has a series of gear teeth 45 adapted for meshing with a pinion 46 keyed to a shaft 4'! rotatable in bearing 48 carried by the frame Ill. The drum I6 is also secured to the shaft 41 and therefore rotates with the pinion 46.

Located at the left of the gear teeth 45 and. mounted on and moving with the segment is a locking dwell arm 6|! having an arcuate surface 6| concentric with the axis 4|. This dwell as shown in Fig. 1 extends beyond and to the left of the left tooth of the section 45 and is adapted for engagement with a lock 52 also having an arcuate concave surface 53' of the same radius as the surface 5|. The lock 52 and pinion 46 are both fast with respect to the shaft 41 and drum l6. The dwell 66 does not extend for the whole length of the segment but is comparatively short, terminating as suggested in the drawing at the left hand tooth of the segment. The locking surface 6 comes into operation when the needle is to be held temporarily at rest out of the shed while the lay beats up.

As; already stated I may also use a second dwell arm 50 on the right end of the segment, the second arm being similar in construction to the dwell 60 and having an arcuate surface 5| concentric with axis 4| and adapted for cooperation with the lock 52.

When the needle is fully inserted into the shed the surface 53 of the lock will engage the surface 5| of dwell arm 56 as shown in Figs. 1 and 3. When the crank arm 34 rises from the position of Fig. 1 the segment will move to the right and the dwell 50 will slide to the right under the 'lock 52.

After a short travel of the crank arm the first, or

right hand tooth of the section 45'will engage the pinion 46 and by this time the left hand end of the dwell 59 will have arrived approximately at a point one line connecting the axes 4| and 41. Hence the lock is free to turn with the pinion when the latter is: rotated by the teeth of the segment. This position is indicated diagrammatically in Fig. 4 of the drawing. 7

As the crank arm 34 rotates in the direction of arrow (1, Fig. l, the segment will continue to move to the right and the pinion 46 will be rotated the desired number of times, the lock 52 turning therewith. Fig. 5 shows an intermediate position between the beginning and ending of the working stroke of the segment with the crank moving the segment with an accelerating rate of speed. Rotation of'the pinion turns the drum and the latter unwinds one end of the cable l3, and winds up the other end, thereby causing sliding movement of the carriage l2 along the rail H to the right as viewed in Fig. l to withdraw the needle N from the warp shed not shown. 7

When the last or left hand tooth 45 leaves or is about to leave the pinion the lock 52 will assume an angular'position which permits the surface 6| of dwell 60 to slide under the surface 53 of the look, after which continued motion of the struction, the large beveled gear 3| having teeth crank arm 34 will move the dwell. 60 under the look without causing rotation of the pinion 46, as suggested in Fig. 6. At this time the needle is withdrawn from the shed and the lay beats up the weft laid by the needle.

Continued motion of the crank arm 34 will now start a left hand motion of the segment and cause the left hand'tooth thereof'to engage the pinion 46 at approximately the same time that the inner or right end of dwell 60 arrives on the line joining centers 4| and 41. The lock 52 therefore no longer restrains the pinion and the latter has a reverse motion to move the needle into the shed. The segment and pinion will again pass through the position suggested by Fig. 4 and as the arm 34 approaches alignment with the connector 42 the surface 5| will slide under surface 53 of the lock and hold the pinion 46 against rotation during the latter part of the left hand motion of the segment.

The amount of dwell on the part of the needle, which is determined by the time during which the teeth 45 move while out of mesh with the pinion.46, can be determined by changing the length of connector 42-.

From the foregoing it will be seen that I have provided a needle motion for Axminster looms wherein the heavy parts, such as the bevel gear 3| and parts driven thereby, are moved continu ously, but the needle is given its desired dwell periods while the lay is beating up weft because of cooperation of the dwells 50 and 60 with the lock 52. It will further be seen that the segment constitutes a member having working and locking strokes during the first of which the drum is turned to cause motion of the needle and during the second of which the drum is locked against rotation while the segment continues to move. As previously stated the dwell 50 is not necessary but is described in order to indicate how the neepinion fixed with respect to the drum, an arcuate set of teeth to mesh with the pinion, alocking surface concentric with the arcuate teeth and moving therewith and extending beyond the teeth in the direction of motion of the latter, and a lock rotating with the pinion and having a curved surface to engage said concentric surface to prevent rotation of the pinion when said concentric surface moves with respect to the lock.

' 2. In a needle motion for an Axminster loom, a needle actuating drum to be rotated, a shaft to which the drum is secured, a pinion secured to the shaft, a constantly rotating actuator member, a

rack having gear teeth to mesh with the pinion,

connections between the actuator member and rack'to reciprocate the latter and give the same a stroke the first part of which is needle actuating and the last part of which is non-actuating with respect to the needle, means moving with the rack presenting a locking surface extending beyond the teeth of the rack, and a lock rotating with the pinion and having a surface to engage the locking surface of the rack, the actuator member causing the dle may. be brought to rest an appreciable period toothed part of the rack to rotate the pinion during the needle actuating part of the stroke of said rack and causing engagement of the locking surface of the segment and the lock of the pinion to prevent rotation of the pinion during the nonactuating part of the stroke of the rack.

3. In a needle motion for an Axminster loom, a needle actuating drum to be rotated, a shaft to which the drum is secured, a pinion secured to the shaft, a constantly rotating actuator member, a segment gear to mesh with the pinion, a connector between the actuator member and segment to reciprocate the latter as the member rotates and give said segment a stroke the first part of which is working and the last part of which is non-working, means on the segment presenting an arcuate locking surface, and a lock secured to and rotating with the pinion for engagement with the locking surface, the actuator member to cause the segment to rotate the pinion during the working part of the stroke of the segment and thereafter cause engagement of the locking surface of the segment with the locking means of the pinion during the non-working part of the stroke of the segment.

4. In a needle motion for an Axminster loom, a needle actuating drum to be rotated, a shaft to which the drum is secured, a pinion secured to the shaft, a constantly rotating actuator memher, a segment gear to mesh with the pinion, a pivot for the latter, a connector between the actuator member and segment gear to reciprocate the latter about the pivot and give the segment a stroke the first part of which is needle actuating and the last part of which is non-actuating with respect to the needle, means, on the segment presenting a locking arcuate surface concentric with the pivot, and a lock secured to and moving with the pinion having an arcuate surface to engage the locking surface, said actuator member causing the segment to rotate the gear during the needle actuating part of the stroke and causing cooperation between the locking surface of the segment and the lock of the pinion to prevent rotation of the latter during the nonactuating part of the stroke of the segment.

5. In a needle motion for an Axminster loom, a

needle actuating drum to be rotated, a pinion fixed with respect to and rotating with the drum, a segment gear to mesh with and rotate the pinion, a pivot for the segment, a constantly rotating actuator connected to the segment and giving the latter a stroke the first part of which is a Working stroke to rotate the pinion, means moving with the segment presenting a locking surface concentric with said pivot, and a lock fixed with respect to and rotating with the pinion and having an arcuate surface of substantially the same radius as the surface of the said first locking surface, said first locking surface extending beyond the teeth of the segment and. brought into locking relationship with respect to the lock moving with the pinion by motion of said segment, the locking surfaces when in engagement effective to prevent rotation of the pinion while the segment moves after the conclusion of the working part of the stroke.

6. In a needle motion for an Axminster loom, a needle actuating drum to be rotated, a shaft to which the drum is secured, a pinion secured to the shaft, a constantly rotating crank arm, a segment gear to mesh with the pinion, a pivot for the segment gear, a connector between the crank arm and the segment to reciprocate the latter, each continuous motion of the segment to have a needle actuating part and a needle non-actuating part derived from the crank arm, means carried by the segment to extend beyond the teeth thereof presenting a locking surface concentric with the pivot, and a lock secured to the pinion and having an arcuate surface of the same radius as that of the locking surface on the segment, the crank arm to cause the teeth of the segment to rotate the pinion during the needle actuating part of the continuous motion of said segment, and the crank arm to move the locking surface of the segment into engagement with the arcuate surface of the look at the conclusion of the needle actuating stroke to prevent rotation of the pinion throughout the nonactuating part of the continuous motion of the segment.

WILLIAM W. ROBERTSON. 

